Quantitative aspects of periglacial slope deposits in southwest England
DOI:
https://doi.org/10.26485/BP/1976/25/4Keywords:
solifluction, granulometric analysis, preferred orientationAbstract
The aim of this paper is to provide a quantitative description of solifluction deposits in southwest England, with particular focus on differentiating between two principal types. A total of 110 samples from over 70 sites. Granulometric analysis revealed significant variability in sediment characteristics, including differences in mean particle size, skewness, and sorting. In the first case deposit is characterized by very poor sorting, positive skewness, and predominance of angular clasts with a marked downslope preferred orientation. In the second case, deposit contains more silt, shows slightly better sorting, fewer coarse particles, and signs of preferred orientation, indicating the interplay of solifluction and possible aeolian input. The results point to the complex genesis and high heterogeneity of these periglacial slope deposits. No single parameter allows for conclusive classification, but a combination of granulometric features may serve as a diagnostic assemblage for identifying bedrock-derived solifluction deposits.
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